More than 48 million turkeys and chickens have died or were euthanized because of the H5N2 avian flu virus that hit Midwest farms this spring. As a result, nationwide egg production in May dropped 5 percent from last year, according to the U.S. Agriculture Department.

About two-thirds of Rita’s 600 stores have switched from custard to the eggless soft-serve, Moody said, and the rest will follow once their custard stock is depleted. All menu items are still available, except they’ll be made with ice cream instead of custard.

The change didn’t faze customers at a Rita’s stand in downtown Philadelphia on Thursday.

City resident Tracy Morton said she’d heard about the issue on the news but still wasn’t sure if her favorite Rita’s treat would be available to help her cool down on a muggy day. She was happy to find she could still get a Gelati - Italian ice layered between dollops of soft-serve.

“I asked the young lady if they were still making Gelatis, and she said yes. Yay for me!” Morton said. “I don’t taste the difference at all.”

David Gounis said he didn’t know anything about the shortage until he saw a sign posted at the ordering window - and it was welcome news.

“I never could get the custard here because I’m allergic to eggs, so that actually worked for me,” Gounis said.

It’s not clear when Rita’s will be able to switch back to custard, Moody said.

The company is not alone in its egg difficulties. Texas-based chain Whataburger temporarily limited its breakfast-serving hours last month because of the shortage but has since rebuilt its egg supply.